package io.binghe.concurrent.lab06;

import java.time.LocalDate;
import java.time.format.DateTimeFormatter;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.Semaphore;

/**
 * @author binghe
 * @version 1.0.0
 * @description 通过DateTimeFormatter类解决线程安全问题
 * DateTimeFormatter类是线程安全的，可以在高并发场景下直接使用DateTimeFormatter类来处理日期的格式化操作
 * 使用DateTimeFormatter类来处理日期的格式化操作运行效率比较高，推荐在高并发业务场景的生产环境使用。
 */
public class SimpleDateFormatTest07 {
    //执行总次数
    private static final int EXECUTE_COUNT = 1000;
    //同时运行的线程数量
    private static final int THREAD_COUNT = 20;

    private static DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyy-MM-dd");

    public static void main(String[] args) throws InterruptedException {
        final Semaphore semaphore = new Semaphore(THREAD_COUNT);
        final CountDownLatch countDownLatch = new CountDownLatch(EXECUTE_COUNT);
        ExecutorService executorService = Executors.newCachedThreadPool();
        for (int i = 0; i < EXECUTE_COUNT; i++){
            executorService.execute(() -> {
                try {
                    semaphore.acquire();
                    try {
                        LocalDate.parse("2020-01-01", formatter);
                    }catch (Exception e){
                        System.out.println("线程：" + Thread.currentThread().getName() + " 格式化日期失败");
                        e.printStackTrace();
                        System.exit(1);
                    }
                    semaphore.release();
                } catch (InterruptedException e) {
                    System.out.println("信号量发生错误");
                    e.printStackTrace();
                    System.exit(1);
                }
                countDownLatch.countDown();
            });
        }
        countDownLatch.await();
        executorService.shutdown();
        System.out.println("所有线程格式化日期成功");
    }
}
